Beijing has decided to extend its post-Olympic road restrictions for another year until April 2010 to reduce the traffic congestion and air pollution in the city.

The restrictions, based on an odd and even number license plate system, were first introduced by the Beijing Municipal Committee of Communication during the Olympics and take nearly 20% of city vehicles off the road, the Xinhua news agency reported.

A fifth of Beijing’s private vehicles and a third of official cars will continue to be banned from entering the controlled zone every week day. Emergency and public service vehicles, along with mass transit vehicles, are not affected.

The city’s Environmental Protection Bureau has estimated that pollutant levels have dropped by 10%, which will help the city meet emissions standards achieved across Europe.

As results of the restrictions during the post-Olympic period were fruitful the people of Beijing support the continuation of rules, the agency said.